# WHATPORT(5051)

## NAME

port 5051 — Apache Mesos agent (registered as ita-agent) — The Mesos agent port in modern clusters; registered to Symantec's Intruder Alert agent.

Protocol: TCP/UDP  
IANA registry

## DESCRIPTION

IANA registers 5051 as ita-agent, the agent side of Symantec's Intruder Alert host intrusion detection product, which is long discontinued. What you find on 5051 today is normally an Apache Mesos agent, whose default `--port` is 5051 while the master uses 5050. The agent exposes HTTP endpoints describing the tasks and executors running on that host.

## EXPOSURE

**Do not expose.** A Mesos agent endpoint reveals what is running on the node and is part of the cluster control path; keep it on the internal network alongside the master.

## CHECK

```sh
curl -s http://TARGET:5051/state | head -c 400
```

## SEE ALSO

- docs — [Apache Mesos — Master and Agent Options (--port defaults)](https://mesos.apache.org/documentation/latest/configuration/master-and-agent/) (mesos.apache.org)
- iana — [IANA port registry — 5051 (ita-agent)](https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=5051) (iana.org)

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HTML: <https://whatport.net/5051/> · JSON: <https://whatport.net/5051.json> · full dataset: <https://whatport.net/ports.json>